Aspirator

Abstract

An aspirator for inflating inflatable devices such as aircraft emergency evacuation slides and life rafts using a quantity of primary gas that is stored in a tank that within the aspirator entrains a secondary gas, typically outside air, as the primary gas flows through the aspirator thereby producing sufficient gas to inflate a large inflatable structure or device as described above. The aspirator typically has injectors therein which act to promote the entrainment of large quantities of the secondary fluid using small quantities of the primary fluid thereby resulting in a large combined flow of gas forcibly flowing into the inflatable structure.

What is claimed is: 
     
       1. An aspirator assembly for use in inflating an inflatable device comprising: an outer body having a main bore with an inner surface and peripheral openings extending through the outer body;   a mixing tube telescopically positioned within the main bore and having an outer surface which includes a first diameter section and a second diameter section; and   a seal fluidly sealing the outer surface of the mixing tube to the inner surface of the main bore in a manner permitting the mixing tube to telescope within the main bore while maintaining the fluid seal, and wherein seal is of a diameter that allows for reduced drag of the mixing tube against the main bore when the seal is adjacent the first diameter section while providing for sufficient sealing when the seal is adjacent the second diameter section.   
     
     
       2. The aspirator assembly as defined in claim 1 wherein the seal is a polymer seal of a non-uniform cross section. 
     
     
       3. The aspirator assembly as defined in claim 2 wherein the polymer seal is a rubber seal of at least one of a reclined L-shaped and a U-shaped cross section. 
     
     
       4. The aspirator assembly as defined in claim 1 wherein the seal is an annular ring of a U-shaped cross section. 
     
     
       5. The aspirator assembly as defined in claim 1 further comprising an injector gasket for fluidly sealing the mixing tube to the outer body when the mixing tube is in an unextended position resulting in the mixing tube sealing off the peripheral openings, and where lip functions to stop the mixing tube from telescoping further when the mixing tube is fully extended. 
     
     
       6. The aspirator assembly as defined in claim 1 further comprising an injector body positioned within the main bore and providing a passage therein through which a primary fluid flows during aspiration. 
     
     
       7. The aspirator assembly as defined in claim 6 wherein an aspirator piston is biased within the passage in a closed manner whereby the release of the primary fluid overcomes the bias and moves the piston to provide fluid flow into injector body and out air injectors therein into the mixing tube where aspiration occurs with a secondary fluid. 
     
     
       8. The aspirator assembly as defined in claim 7 wherein the aspirator piston is a first piston seated within a second larger piston. 
     
     
       9. The aspirator assembly as defined in claim 1 further comprising a regulator fluidly connected to an inlet in the outer body through which a primary fluid is provided for aspiration. 
     
     
       10. The aspirator assembly as defined in claim 9 wherein the regulator includes a spring biased regulator piston therein, the regulator piston including a tapered head. 
     
     
       11. An aspirator assembly for use in inflating an inflatable device comprising: an outer body having a main bore with an inner surface and peripheral openings extending through the outer body;   a mixing tube telescopically positioned within the main bore and having a tube lip with a tube body extending therefrom and having an outer surface, the tube body having a first diameter section extending between the tube lip and a second diameter section which is of a larger diameter than the first diameter section; and   a seal fluidly sealing the outer surface of the mixing tube to the inner surface of the main bore in a manner permitting the mixing tube to telescope within the main bore while maintaining the fluid seal.   
     
     
       12. The aspirator assembly as defined in claim 11 further comprising a taper connecting the first and second diameter sections. 
     
     
       13. The aspirator assembly as defined in claim 11 wherein the seal is a polymer seal of a non-uniform cross section. 
     
     
       14. The aspirator assembly as defined in claim 11 wherein the seal is an annular ring of a U-shaped cross section. 
     
     
       15. The aspirator assembly as defined in claim 1 further comprising an injector gasket for fluidly sealing the mixing tube to the outer body when the mixing tube is in an unextended position resulting in the mixing tube sealing off the peripheral openings, and where lip functions to stop the mixing tube from telescoping further when the mixing tube is fully extended. 
     
     
       16. An aspirator assembly for use in inflating an inflatable device comprising: an outer body having a main bore with an inner surface and peripheral openings extending through the outer body;   a mixing tube telescopically positioned within the main bore and having an outer surface which includes a first diameter section and a second diameter section;   a seal fluidly sealing the outer surface of the mixing tube to the inner surface of the main bore in a manner permitting the mixing tube to telescope within the main bore while maintaining the fluid seal; and   wherein the mixing tube includes the first diameter section and the second diameter section of a larger diameter whereby the seal and diameter sections are correlated such that the first diameter section is adjacent the seal during any telescopic movement of the mixing tube while the second diameter section is adjacent the seal when the mixing tube is biased closed.   
     
     
       17. The aspirator assembly as defined in claim 16 further comprising a taper connecting the first and second diameter sections. 
     
     
       18. The aspirator assembly as defined in claim 16 wherein the seal is a polymer seal of a non-uniform cross section. 
     
     
       19. The aspirator assembly as defined in claim 16 wherein the seal is an annular ring of a U-shaped cross section. 
     
     
       20. The aspirator assembly as defined in claim 16 further comprising an injector gasket for fluidly sealing the mixing tube to the outer body when the mixing tube is in an unextended position resulting in the mixing tube sealing off the peripheral openings, and where lip functions to stop the mixing tube from telescoping further when the mixing tube is fully extended.